diff --git a/demo/markdownlint-browser.js b/demo/markdownlint-browser.js
index 471f04e7..8b3f66fe 100644
--- a/demo/markdownlint-browser.js
+++ b/demo/markdownlint-browser.js
@@ -927,28 +927,34 @@ module.exports.applyFixes = applyFixes;
  * @param {number} lineIndex Line index to check.
  * @param {string} search Text to search for.
  * @param {string} replace Text to replace with.
+ * @param {number} [instance] Instance on the line (1-based).
  * @returns {Object} Range and fixInfo wrapper.
  */
-function getRangeAndFixInfoIfFound(lines, lineIndex, search, replace) {
-    var range = null;
-    var fixInfo = null;
-    var searchIndex = lines[lineIndex].indexOf(search);
-    if (searchIndex !== -1) {
-        var column = searchIndex + 1;
-        var length = search.length;
-        range = [column, length];
-        fixInfo = {
-            "editColumn": column,
-            "deleteCount": length,
-            "insertText": replace
+module.exports.getRangeAndFixInfoIfFound =
+    function (lines, lineIndex, search, replace, instance) {
+        if (instance === void 0) { instance = 1; }
+        var range = null;
+        var fixInfo = null;
+        var searchIndex = -1;
+        while (instance > 0) {
+            searchIndex = lines[lineIndex].indexOf(search, searchIndex + 1);
+            instance--;
+        }
+        if (searchIndex !== -1) {
+            var column = searchIndex + 1;
+            var length = search.length;
+            range = [column, length];
+            fixInfo = {
+                "editColumn": column,
+                "deleteCount": length,
+                "insertText": replace
+            };
+        }
+        return {
+            range: range,
+            fixInfo: fixInfo
         };
-    }
-    return {
-        range: range,
-        fixInfo: fixInfo
     };
-}
-module.exports.getRangeAndFixInfoIfFound = getRangeAndFixInfoIfFound;
 /**
  * Gets the next (subsequent) child token if it is of the expected type.
  *
@@ -4411,6 +4417,8 @@ module.exports = {
     "tags": ["emphasis"],
     "function": function MD049(params, onError) {
         var expectedStyle = String(params.config.style || "consistent");
+        var lastLineNumber = -1;
+        var instances = new Map();
         forEachInlineChild(params, "em_open", function (token, parent) {
             var lineNumber = token.lineNumber, markup = token.markup;
             var markupStyle = emphasisOrStrongStyleFor(markup);
@@ -4425,7 +4433,12 @@ module.exports = {
                     var actual = "".concat(markup).concat(content).concat(markup);
                     var expectedMarkup = (expectedStyle === "asterisk") ? "*" : "_";
                     var expected = "".concat(expectedMarkup).concat(content).concat(expectedMarkup);
-                    rangeAndFixInfo = getRangeAndFixInfoIfFound(params.lines, lineNumber - 1, actual, expected);
+                    if (lastLineNumber !== lineNumber) {
+                        lastLineNumber = lineNumber;
+                        instances.clear();
+                    }
+                    instances.set(expected, (instances.get(expected) || 0) + 1);
+                    rangeAndFixInfo = getRangeAndFixInfoIfFound(params.lines, lineNumber - 1, actual, expected, instances.get(expected));
                 }
                 addError(onError, lineNumber, "Expected: ".concat(expectedStyle, "; Actual: ").concat(markupStyle), null, rangeAndFixInfo.range, rangeAndFixInfo.fixInfo);
             }
@@ -4452,6 +4465,8 @@ module.exports = {
     "tags": ["emphasis"],
     "function": function MD050(params, onError) {
         var expectedStyle = String(params.config.style || "consistent");
+        var lastLineNumber = -1;
+        var instances = new Map();
         forEachInlineChild(params, "strong_open", function (token, parent) {
             var lineNumber = token.lineNumber, markup = token.markup;
             var markupStyle = emphasisOrStrongStyleFor(markup);
@@ -4466,7 +4481,12 @@ module.exports = {
                     var actual = "".concat(markup).concat(content).concat(markup);
                     var expectedMarkup = (expectedStyle === "asterisk") ? "**" : "__";
                     var expected = "".concat(expectedMarkup).concat(content).concat(expectedMarkup);
-                    rangeAndFixInfo = getRangeAndFixInfoIfFound(params.lines, lineNumber - 1, actual, expected);
+                    if (lastLineNumber !== lineNumber) {
+                        lastLineNumber = lineNumber;
+                        instances.clear();
+                    }
+                    instances.set(expected, (instances.get(expected) || 0) + 1);
+                    rangeAndFixInfo = getRangeAndFixInfoIfFound(params.lines, lineNumber - 1, actual, expected, instances.get(expected));
                 }
                 addError(onError, lineNumber, "Expected: ".concat(expectedStyle, "; Actual: ").concat(markupStyle), null, rangeAndFixInfo.range, rangeAndFixInfo.fixInfo);
             }
diff --git a/helpers/helpers.js b/helpers/helpers.js
index 95d508d6..9bd7ccde 100644
--- a/helpers/helpers.js
+++ b/helpers/helpers.js
@@ -950,28 +950,33 @@ module.exports.applyFixes = applyFixes;
  * @param {number} lineIndex Line index to check.
  * @param {string} search Text to search for.
  * @param {string} replace Text to replace with.
+ * @param {number} [instance] Instance on the line (1-based).
  * @returns {Object} Range and fixInfo wrapper.
  */
-function getRangeAndFixInfoIfFound(lines, lineIndex, search, replace) {
-  let range = null;
-  let fixInfo = null;
-  const searchIndex = lines[lineIndex].indexOf(search);
-  if (searchIndex !== -1) {
-    const column = searchIndex + 1;
-    const length = search.length;
-    range = [ column, length ];
-    fixInfo = {
-      "editColumn": column,
-      "deleteCount": length,
-      "insertText": replace
+module.exports.getRangeAndFixInfoIfFound =
+  (lines, lineIndex, search, replace, instance = 1) => {
+    let range = null;
+    let fixInfo = null;
+    let searchIndex = -1;
+    while (instance > 0) {
+      searchIndex = lines[lineIndex].indexOf(search, searchIndex + 1);
+      instance--;
+    }
+    if (searchIndex !== -1) {
+      const column = searchIndex + 1;
+      const length = search.length;
+      range = [ column, length ];
+      fixInfo = {
+        "editColumn": column,
+        "deleteCount": length,
+        "insertText": replace
+      };
+    }
+    return {
+      range,
+      fixInfo
     };
-  }
-  return {
-    range,
-    fixInfo
   };
-}
-module.exports.getRangeAndFixInfoIfFound = getRangeAndFixInfoIfFound;
 
 /**
  * Gets the next (subsequent) child token if it is of the expected type.
diff --git a/lib/md049.js b/lib/md049.js
index 4d36df55..74aaf809 100644
--- a/lib/md049.js
+++ b/lib/md049.js
@@ -11,6 +11,8 @@ module.exports = {
   "tags": [ "emphasis" ],
   "function": function MD049(params, onError) {
     let expectedStyle = String(params.config.style || "consistent");
+    let lastLineNumber = -1;
+    const instances = new Map();
     forEachInlineChild(params, "em_open", (token, parent) => {
       const { lineNumber, markup } = token;
       const markupStyle = emphasisOrStrongStyleFor(markup);
@@ -27,8 +29,17 @@ module.exports = {
           const actual = `${markup}${content}${markup}`;
           const expectedMarkup = (expectedStyle === "asterisk") ? "*" : "_";
           const expected = `${expectedMarkup}${content}${expectedMarkup}`;
+          if (lastLineNumber !== lineNumber) {
+            lastLineNumber = lineNumber;
+            instances.clear();
+          }
+          instances.set(expected, (instances.get(expected) || 0) + 1);
           rangeAndFixInfo = getRangeAndFixInfoIfFound(
-            params.lines, lineNumber - 1, actual, expected
+            params.lines,
+            lineNumber - 1,
+            actual,
+            expected,
+            instances.get(expected)
           );
         }
         addError(
diff --git a/lib/md050.js b/lib/md050.js
index 2ca9260e..28c53f91 100644
--- a/lib/md050.js
+++ b/lib/md050.js
@@ -11,6 +11,8 @@ module.exports = {
   "tags": [ "emphasis" ],
   "function": function MD050(params, onError) {
     let expectedStyle = String(params.config.style || "consistent");
+    let lastLineNumber = -1;
+    const instances = new Map();
     forEachInlineChild(params, "strong_open", (token, parent) => {
       const { lineNumber, markup } = token;
       const markupStyle = emphasisOrStrongStyleFor(markup);
@@ -27,8 +29,17 @@ module.exports = {
           const actual = `${markup}${content}${markup}`;
           const expectedMarkup = (expectedStyle === "asterisk") ? "**" : "__";
           const expected = `${expectedMarkup}${content}${expectedMarkup}`;
+          if (lastLineNumber !== lineNumber) {
+            lastLineNumber = lineNumber;
+            instances.clear();
+          }
+          instances.set(expected, (instances.get(expected) || 0) + 1);
           rangeAndFixInfo = getRangeAndFixInfoIfFound(
-            params.lines, lineNumber - 1, actual, expected
+            params.lines,
+            lineNumber - 1,
+            actual,
+            expected,
+            instances.get(expected)
           );
         }
         addError(
diff --git a/test/detailed-results-MD041-MD050.json b/test/detailed-results-MD041-MD050.json
index 1016951d..606024a6 100644
--- a/test/detailed-results-MD041-MD050.json
+++ b/test/detailed-results-MD041-MD050.json
@@ -1,5 +1,6 @@
 {
   "default": true,
+  "MD013": false,
   "MD043": {
     "headings": [
       "# Heading"
diff --git a/test/detailed-results-MD041-MD050.md b/test/detailed-results-MD041-MD050.md
index d4b6fd0b..6c8cac05 100644
--- a/test/detailed-results-MD041-MD050.md
+++ b/test/detailed-results-MD041-MD050.md
@@ -42,4 +42,8 @@ strong **emphasis
 spanning** many
 lines
 
+Inconsistent _double_ text _interleaved_ text _double_ _interleaved_ emphasis.
+
+Inconsistent **double** text **interleaved** text **double** **interleaved** strong emphasis.
+
 Missing newline character
\ No newline at end of file
diff --git a/test/detailed-results-MD041-MD050.md.fixed b/test/detailed-results-MD041-MD050.md.fixed
index a26adc9b..056612f1 100644
--- a/test/detailed-results-MD041-MD050.md.fixed
+++ b/test/detailed-results-MD041-MD050.md.fixed
@@ -42,4 +42,8 @@ strong **emphasis
 spanning** many
 lines
 
+Inconsistent *double* text *interleaved* text *double* *interleaved* emphasis.
+
+Inconsistent __double__ text __interleaved__ text __double__ __interleaved__ strong emphasis.
+
 Missing newline character
diff --git a/test/detailed-results-MD041-MD050.results.json b/test/detailed-results-MD041-MD050.results.json
index e4c35d34..eb8f6e2e 100644
--- a/test/detailed-results-MD041-MD050.results.json
+++ b/test/detailed-results-MD041-MD050.results.json
@@ -78,7 +78,7 @@
     "fixInfo": null
   },
   {
-    "lineNumber": 45,
+    "lineNumber": 49,
     "ruleNames": [
       "MD043",
       "required-headings",
@@ -178,7 +178,7 @@
     "fixInfo": null
   },
   {
-    "lineNumber": 45,
+    "lineNumber": 49,
     "ruleNames": [
       "MD047",
       "single-trailing-newline"
@@ -262,6 +262,86 @@
       "emphasis-style"
     ]
   },
+  {
+    "errorContext": null,
+    "errorDetail": "Expected: asterisk; Actual: underscore",
+    "errorRange": [
+      14,
+      8
+    ],
+    "fixInfo": {
+      "deleteCount": 8,
+      "editColumn": 14,
+      "insertText": "*double*"
+    },
+    "lineNumber": 45,
+    "ruleDescription": "Emphasis style should be consistent",
+    "ruleInformation": "https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/Rules.md#md049",
+    "ruleNames": [
+      "MD049",
+      "emphasis-style"
+    ]
+  },
+  {
+    "errorContext": null,
+    "errorDetail": "Expected: asterisk; Actual: underscore",
+    "errorRange": [
+      28,
+      13
+    ],
+    "fixInfo": {
+      "deleteCount": 13,
+      "editColumn": 28,
+      "insertText": "*interleaved*"
+    },
+    "lineNumber": 45,
+    "ruleDescription": "Emphasis style should be consistent",
+    "ruleInformation": "https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/Rules.md#md049",
+    "ruleNames": [
+      "MD049",
+      "emphasis-style"
+    ]
+  },
+  {
+    "errorContext": null,
+    "errorDetail": "Expected: asterisk; Actual: underscore",
+    "errorRange": [
+      47,
+      8
+    ],
+    "fixInfo": {
+      "deleteCount": 8,
+      "editColumn": 47,
+      "insertText": "*double*"
+    },
+    "lineNumber": 45,
+    "ruleDescription": "Emphasis style should be consistent",
+    "ruleInformation": "https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/Rules.md#md049",
+    "ruleNames": [
+      "MD049",
+      "emphasis-style"
+    ]
+  },
+  {
+    "errorContext": null,
+    "errorDetail": "Expected: asterisk; Actual: underscore",
+    "errorRange": [
+      56,
+      13
+    ],
+    "fixInfo": {
+      "deleteCount": 13,
+      "editColumn": 56,
+      "insertText": "*interleaved*"
+    },
+    "lineNumber": 45,
+    "ruleDescription": "Emphasis style should be consistent",
+    "ruleInformation": "https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/Rules.md#md049",
+    "ruleNames": [
+      "MD049",
+      "emphasis-style"
+    ]
+  },
   {
     "errorContext": null,
     "errorDetail": "Expected: underscore; Actual: asterisk",
@@ -314,5 +394,85 @@
       "MD050",
       "strong-style"
     ]
+  },
+  {
+    "errorContext": null,
+    "errorDetail": "Expected: underscore; Actual: asterisk",
+    "errorRange": [
+      14,
+      10
+    ],
+    "fixInfo": {
+      "deleteCount": 10,
+      "editColumn": 14,
+      "insertText": "__double__"
+    },
+    "lineNumber": 47,
+    "ruleDescription": "Strong style should be consistent",
+    "ruleInformation": "https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/Rules.md#md050",
+    "ruleNames": [
+      "MD050",
+      "strong-style"
+    ]
+  },
+  {
+    "errorContext": null,
+    "errorDetail": "Expected: underscore; Actual: asterisk",
+    "errorRange": [
+      30,
+      15
+    ],
+    "fixInfo": {
+      "deleteCount": 15,
+      "editColumn": 30,
+      "insertText": "__interleaved__"
+    },
+    "lineNumber": 47,
+    "ruleDescription": "Strong style should be consistent",
+    "ruleInformation": "https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/Rules.md#md050",
+    "ruleNames": [
+      "MD050",
+      "strong-style"
+    ]
+  },
+  {
+    "errorContext": null,
+    "errorDetail": "Expected: underscore; Actual: asterisk",
+    "errorRange": [
+      51,
+      10
+    ],
+    "fixInfo": {
+      "deleteCount": 10,
+      "editColumn": 51,
+      "insertText": "__double__"
+    },
+    "lineNumber": 47,
+    "ruleDescription": "Strong style should be consistent",
+    "ruleInformation": "https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/Rules.md#md050",
+    "ruleNames": [
+      "MD050",
+      "strong-style"
+    ]
+  },
+  {
+    "errorContext": null,
+    "errorDetail": "Expected: underscore; Actual: asterisk",
+    "errorRange": [
+      62,
+      15
+    ],
+    "fixInfo": {
+      "deleteCount": 15,
+      "editColumn": 62,
+      "insertText": "__interleaved__"
+    },
+    "lineNumber": 47,
+    "ruleDescription": "Strong style should be consistent",
+    "ruleInformation": "https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/Rules.md#md050",
+    "ruleNames": [
+      "MD050",
+      "strong-style"
+    ]
   }
 ]
\ No newline at end of file