diff --git a/crates/ruff_linter/resources/test/fixtures/pep8_naming/N815.py b/crates/ruff_linter/resources/test/fixtures/pep8_naming/N815.py
index d3578d3cfbd7d..41a9f46fd8f96 100644
--- a/crates/ruff_linter/resources/test/fixtures/pep8_naming/N815.py
+++ b/crates/ruff_linter/resources/test/fixtures/pep8_naming/N815.py
@@ -21,3 +21,10 @@ class D(TypedDict):
     mixedCase: bool
     _mixedCase: list
     mixed_Case: set
+
+class E(D):
+    lower: int
+    CONSTANT: str
+    mixedCase: bool
+    _mixedCase: list
+    mixed_Case: set
diff --git a/crates/ruff_linter/src/checkers/ast/analyze/expression.rs b/crates/ruff_linter/src/checkers/ast/analyze/expression.rs
index 9e85625e87eba..f7fb21373d889 100644
--- a/crates/ruff_linter/src/checkers/ast/analyze/expression.rs
+++ b/crates/ruff_linter/src/checkers/ast/analyze/expression.rs
@@ -223,14 +223,10 @@ pub(crate) fn expression(expr: &Expr, checker: &mut Checker) {
                         }
                     }
                     if checker.enabled(Rule::MixedCaseVariableInClassScope) {
-                        if let ScopeKind::Class(ast::StmtClassDef { arguments, .. }) =
-                            &checker.semantic.current_scope().kind
+                        if let ScopeKind::Class(class_def) = &checker.semantic.current_scope().kind
                         {
                             pep8_naming::rules::mixed_case_variable_in_class_scope(
-                                checker,
-                                expr,
-                                id,
-                                arguments.as_deref(),
+                                checker, expr, id, class_def,
                             );
                         }
                     }
diff --git a/crates/ruff_linter/src/rules/pep8_naming/helpers.rs b/crates/ruff_linter/src/rules/pep8_naming/helpers.rs
index 068c4b143b95e..e94ace527c638 100644
--- a/crates/ruff_linter/src/rules/pep8_naming/helpers.rs
+++ b/crates/ruff_linter/src/rules/pep8_naming/helpers.rs
@@ -1,8 +1,8 @@
 use itertools::Itertools;
 
 use ruff_python_ast::name::UnqualifiedName;
-use ruff_python_ast::{self as ast, Arguments, Expr, Stmt};
-use ruff_python_semantic::SemanticModel;
+use ruff_python_ast::{self as ast, Expr, Stmt};
+use ruff_python_semantic::{analyze, SemanticModel};
 use ruff_python_stdlib::str::{is_cased_lowercase, is_cased_uppercase};
 
 pub(super) fn is_camelcase(name: &str) -> bool {
@@ -86,16 +86,13 @@ pub(super) fn is_type_alias_assignment(stmt: &Stmt, semantic: &SemanticModel) ->
 }
 
 /// Returns `true` if the statement is an assignment to a `TypedDict`.
-pub(super) fn is_typed_dict_class(arguments: Option<&Arguments>, semantic: &SemanticModel) -> bool {
+pub(super) fn is_typed_dict_class(class_def: &ast::StmtClassDef, semantic: &SemanticModel) -> bool {
     if !semantic.seen_typing() {
         return false;
     }
 
-    arguments.is_some_and(|arguments| {
-        arguments
-            .args
-            .iter()
-            .any(|base| semantic.match_typing_expr(base, "TypedDict"))
+    analyze::class::any_qualified_name(class_def, semantic, &|qualified_name| {
+        semantic.match_typing_qualified_name(&qualified_name, "TypedDict")
     })
 }
 
diff --git a/crates/ruff_linter/src/rules/pep8_naming/rules/mixed_case_variable_in_class_scope.rs b/crates/ruff_linter/src/rules/pep8_naming/rules/mixed_case_variable_in_class_scope.rs
index 6ebed08650a61..15b11ac894bd1 100644
--- a/crates/ruff_linter/src/rules/pep8_naming/rules/mixed_case_variable_in_class_scope.rs
+++ b/crates/ruff_linter/src/rules/pep8_naming/rules/mixed_case_variable_in_class_scope.rs
@@ -1,7 +1,6 @@
-use ruff_python_ast::{Arguments, Expr};
-
 use ruff_diagnostics::{Diagnostic, Violation};
 use ruff_macros::{derive_message_formats, violation};
+use ruff_python_ast::{self as ast, Expr};
 use ruff_text_size::Ranged;
 
 use crate::checkers::ast::Checker;
@@ -55,7 +54,7 @@ pub(crate) fn mixed_case_variable_in_class_scope(
     checker: &mut Checker,
     expr: &Expr,
     name: &str,
-    arguments: Option<&Arguments>,
+    class_def: &ast::StmtClassDef,
 ) {
     if !helpers::is_mixed_case(name) {
         return;
@@ -64,7 +63,7 @@ pub(crate) fn mixed_case_variable_in_class_scope(
     let parent = checker.semantic().current_statement();
 
     if helpers::is_named_tuple_assignment(parent, checker.semantic())
-        || helpers::is_typed_dict_class(arguments, checker.semantic())
+        || helpers::is_typed_dict_class(class_def, checker.semantic())
     {
         return;
     }